Lint removal system



N0v.21,`1967 'w..s|LvA l 3,353,681

LINT REMOVAL SYSTEM Filed Dec. 6. 1965 5 Sheets-Sheet l Hf 0 0 a j I M40W0 (l `6`\` g (D 0 o l M am o 36 l 2'? 0) a 0 i? 21 i? 0 m Y (D u] o o o25 "bin'll' a J3 :mgl-lnk o w w ,26 o 0 Nov. 21, 1967 -w, C. slm/A3,353,61

LINT REMOVAL SYSTEM Filed Deo. 6,. 1965 3 Sheets-Sheet '2 /A/I/ENTOR./04 /03 W/LL/AM G S/LI/A Filed Deo. 6v. 1965 3 Sheets-Sheet 5 sVsrEMFROM F/L 7' El? JP//V ROTA T/ON (REVERSE) ONE afwas/sf? A M /ZS Wm n. #i/Q nM /m L W W w m d w m M M m Q. V 4

United States Patent Giice 3,353,681 Patented Nov. 21, 1967 3,353,681LIN'I REMOVAL SYSTEM William C. Silva, Herrin, Ill., assignor toBorg-Warner Corporation, Chicago, Ill., a corporation of Illinois FiledDec. 6, 1965, Ser. No. 511,615 9 Claims. (Cl. 210-355) This inventionrelates to lint filtering systems for washing machines and the like andmore particularly to lint filtering systems of the self-cleaning orautomatic-cleaning type.

It is desirable to employ lint filtering systems in washing machines andparticularly washing machines of the type adapted to recirculate waterpassing through the clothes during the washing operation. In suchmachines, lint-filtering devices are employed in the recirculationsystem to prevent lint-laden water being returned to the clothescontainer and being deposited on the clothes. In the event the filterdevice must be periodically manually removed to clean the device, itfrequently occurs that this action is neglected with the consequentclogging of the device by the lint may seriously impair therecirculation flow and thereby reduce washing quality.

An object of the invention is to provide a lint-filtering system forwashing machines of the recirculating type and which is self-cleaningduring operation of the machine.

Another object of the invention is to provide a lintfiltering system ofthe above type wherein lint-laden water is continuously filtered duringrecirculation and provided with means for automatically removing thecollected lint from the filter for disposal exteriorly of the machine toa drain upon completion of the washing operation.

Another object of the invention is to provide a lintfiltering device ofthe type described and comprising mechanical means, solely responsive tothe water flow, to remove the lint from the device upon termination ofthe washing operation thereby eliminating the use of costly, andfailure-possibility, of electrically-operated actuating units for thispurpose.

Another object of the invention is to provide a selfcleaninglint-filtering device capable of providing filtering action during oneor more agitator and water-extraction speeds and irrespective of thewater levels employed in automatic washing machines.

A specific object of the invention is to provide a lintfiltering devicefor laundry machines of the recirculating type and comprisinglint-screening teeth disposed in the recirculation system during theflow of water in one direction in the washing operation, and mechanicalmeans operative, by the flow of water in the opposite direction duringdraining of the wash water from the machine, to strip the lint from theteeth for removal by the Water to the drain.

Further objects, features and advantages of the present invention willbecome apparent from the following detailed description of the presentlypreferred embodiment of the invention, taken in combination with theaccompanying drawings in which:

FIG. 1 is a sectional elevational view of an automatic washing machineembodying the lint filter device of the present invention;

FIG. 2 is a perspective view of the washing machine shown in FIG. l,illustrating the iiuid circulation system embodying the lint filterdevice;

FIG. 3 is a plan view of the washing machine base assembly, taken alongline 3 3 of FIG. l;

FIG. 4 is a sectional view of the pump employed in the fluid circulationsystem of FIG. 2;

FIG. 5 is -a schematic showingof the fluid circulation system shown inFIG. 2;

FIG. 6 is an enlarged vertical sectional elevation of the lint filterdevice; and

FIG. 7 is a sectional view of the lint filter device shown in FIG. 5,taken on line 7-7 of FIG. 6.

Referring now the drawings, FIG. 1 discloses an automatic washer inwhich the present invention finds particular applicability. Theautomatic washer includes an outter cabinet 11 having a top 12 hingedlysupporting a loading and unloading door 14 and carrying a backguard 15on which are mounted controls for the washing machine. A tub 16, havingan annular guard 16a, is provided inside the cabinet 11 having a bottom17 and a top opening 18 beneath the door 14. Forming a container forclothes or other articles to be washed is a perforate basket 19 having abottom wall 20, top opening 20a and a substantially cylindrical sidewall 21. The basket is mounted on a vertically disposed center post 22.

To provide for relative rotation between the tub and basket, the bottom20 of the basket is fastened to a center post base 24 by screws 25 (oneof which is shown). The center post base 24 is also connected, by screws25, to a spin hub 26 rotatably journalled in a bearing assembly 28mounted in the tub bottom 17. For feeding water into the tub to wash orrinse the clothes, a fiume 29 (FIG. 2) is provided mounted on the tubcover 16a to direct water into opening 18 of the tub and through theopening 20a of the basket. The flume is connected by a hose and conduit30 to a water input contr-ol valve 31.

To agitate the clothes during washing or rinsing, the basket 19 is heldstationary while an agitator 36 having a plurality of vanes 38 and askirt 39 is oscillated to and fro. The agitator has a central opening 40for receiving the center post 22 and is rotatably supported thereon. Thecenter post remains stationary while the agitator oscil- Y lates.

After the tub has been filled, a wash cycle of operation begins. At thistime, reversible oscillatory drive is transmitted to agitator 36 from amotor 41 through a first drive train including a lower drive assembly42, a transmission 44 and an agitator drive shaft 45. In the exemplaryembodiment, the drive shaft 45 extends centrally through the hollowcenter post 22 and carries a drive block 46 at its upper end. The upperend of the agitator central opening 40 is formed to engage the driveblock 46 so that the two structures turn as a unit. For maintaining theagitator seated on the drive block, a cap 48 is threaded on a stud 49extending from the upper Aend of the drive block 46.

After the wash cycle is completed, wash water is pumped out of themachine and the basket 19 is spun at a relatively high speed to extractwash water from the clothes. The side walls 21 of the basket areperforate so that the water is expelled therethrough. Describing asecond drive train for effecting spin rotation of the basket 19, thelower drive assembly 42 is constructed so as to rotate the transmission44.as a unit including a transmission housing 50. The housing 50 iscoupled to the spin hub 26 which supports the center post 22 and basket19. Accordingly, spinning of the transmission effects rotation of thebasket 19.

Turning to the respective drive trains in the illustrative washingmachine in more detail, the motor 41 is mounted in inverted fashion on abase plate 51 extending across the bottom of the washing machine 10. Themotor has a drive shaft which extends below the mounting plate 51 andcarries a drive pulley which is coupled by a belt 52, in the presentinstance, a V-drive belt, to a pair of driven pulleys 54, 55, one pulley54 coupled to drive the lower.` driveassembly 42 and ythe other pulley55 coupled to drive aftwin impeller pump 56. As explained subsequently,pump 56 operates selectively as a recirculation pump or as a drain pump.Each of the driven pulleys are disposed below the base plate 51 whilethe driven mechanisms, the lower drive assembly 42, and the pump 56 aremounted atop the base plate 51. The driven pulley 54 is suitablyfastened, in the present instance by .a spline and key tit to a maindrive shaft S8 extending upwardly from the pulley 54 through the lowerdrive assembly 42. The upper end of shaft S is coupled via anoverrunning or one-way spring clutch to a transmission including a drivepinion 60. The transmission is shown and described in Gerhardt et alU.S. Patent 2,807,951. The one-way spring clutch provides drive to thetransmission drive pinion 60 to transmit an oscillatory drive to theagitator during forward rotation of drive shaft 58, while disconnectingdrive to pinion 60 during reverse rotation of shaft 58. Accordingly, toeffect oscillation of the agitator, the drive shaft 58, as a part of therst drive train, is rotated. in a forward direction thereby operatingthe one-way clutch so that the gear train in the transmission 44 effectsoscillation of agitator drive shaft 45.

As described, the basket 19 is rotatable with respect to the tub 16. Itis, however, undesirable during the agitation cycle to have the basketfreely moving. On the other hand, washer operation is smoothed and motorstrain is reduced by permitting slight movement of the basket at thepoint where the agitator reverses direction in its oscillationoperation. In addition, following high speed spin of the basket,structure must be provided to slow down the basket. For this purpose,the second drive train includes a brake assembly to retard movement ofthe transmission housing and thereby the basket 19 during agitation (seeFIGS. l, 3). The brake assembly and its operation are the subject of andis disclosed in detail in co-pending application of Clarence M. Overturfand Richard L. Conrath, Ser. No. 371,347, filed lune l, 1964. Ingeneral, the brake assembly 64 includes a brake hub 69 suitably fastenedto a basket-connected tube with the tube and the transmission housing 50operating as a unit, thus by holding the tube stationary thetransmission housing and basket are held against rotation.

To retard basket rotation, the brake hub 69 is surrounded by a brakelining surrounded by a :brake band 75 and tightly held against the hubby the brake band of spring steel. Braking is effected by selectivelyholding the brake band against rotation by engaging it with a brakelatch pivotally mounted on a support bracket 81. The bracket 81 ismounted on a suspension tube 82 supported in a bearing carried in thebrake hub 69.

The brake latch is normally biased as to engage the brake band by abiasing spring. Engagement of the brake is effected during rotation ofthe brake band 75, and therewith basket 19, in either the forward orreverse directions. To engage the brake during forward rotation of thedrive shaft, the agitate direction, the brake band is held by the latchand thereby retarding basket 19 against rotation in either direction.The -brake is also engaged in the reverse direction of rotation of thebrake band, necessary during high speed spin of the basket.

Free rotation of the brake hub and appended structure, i.e.,transmission housing and basket, is permitted by disengaging the latchand the brake band by a solenoid operating the latch against the springbiasing force so that when it is desired to spin the basket, thetransmission housing is freed for rotation by energizing the brakesolenoid and releasing the brake.

The second or spin drive train is selectively operated during reverserotation of the motor by engaging or disengaging a clutch assembly 87.In the present instance, clutch assembly 87 transmits drive from a lowerdrive hub 88 to the brake hub 69 coupled to the transmission housing 50and thereby the basket. The lower drive hub 88 is spline-fitted on themain drive shaft 53. The clutch assembly 87 includes a lower drive shaftor column and an upper driven shaft or column. The lower drive column isan integral extension of the lower drive hub 88. The upper driven columnis a depending extension of the brake hub 69. A one-way clutch springhas respective upper and lower sections extending over the respectiveend portions of the generally abutting upper driven column and lowerdrive column.

The clutch spring is of the coil type and surrounds the respectivecircular drive transmitting columns or shafts. Rotation of the lowerdrive column in one direction (presently, reverse motor direction)causes the clutch spring to tighten and wrap-around both columns. Thiseffects transmission of drive from the lower column to the upper column.Rotation of the lower drive column in the opposite direction (forwardmotor direction) uncoils or loosens the spring so that drive is nottransmitted to the upper column.

Selective driving in the wrap-around or drive direction is effected byuse of control means including annular means coaxial with the seconddrive train taking the form, in the exemplary embodiment, of a clutchshield or sleeve 93 (FIG. 3) extending about the spring and holding aterminating end of the lower spring section overlying a portion of lowerdrive shaft S8. The shield or sleeve 93 and spring are selectively heldagainst rotation by providing, on the upper end of shield 93, engageablemeans, exemplarily shown as a plurality of projecting ears 93a, whichpermit coupling with a selectively-operable pivoted clutch pawl 94. Thepawl 94 is normally biased by a spring 95 so that a projecting finger 96can engage one of the ears 93a. FIG. 3 shows the pawl linger 96disengaged. The result of holding the control shield or sleeve 93stationary is, that even though the spring lits snugly about the lowerdrive shaft or column and the upper driven shaft or column, the springis not tightened and drive is not transmitted between the columns, untilthe spring and shield are released and permitted to rotate with thedrive column.

Describing the structure for selectively engaging the clutch spring 92,the shield 93 is released and the spring is permitted to wrap around therespective drive and driven columns by operation of a solenoid 9S. Itis, of course, understood that the driven column must be rotating in theproper direction to effect tightening of the spring about the respectivecolumns. The solenoid 98 has an armature 99 connected by linkageassembly 100 to the clutch pawl 94. The solenoid acts against the biasspring 95 and pivots the pawl to disengage it from shield 93.

The motor 41 is reversible to rotate pump 55 and main drive shaft S8 ineither direction. The motor has a start winding and a pair of runwindings. Direction of rotation is determined by the relative polaritybetween the start and run windings, i.e., simply by reversing therelative polarity, the rotation of the motor is reversed.

For a more complete description of the agitator basket drive structuresand the brake and clutch controls, reference is made to U.S. Patent2,807,951 and co-pending patent application, Ser. No. 371,312, led Iune1, 1964.

To recirculate water during the washing operation and to drain waterprior to the spinning operation, the pump 56 is provided (see FIG. 4).This is a dual impeller pump having an upper impeller 103 located in thepump chamber 1.0351 and a lower impeller 104 in the pump chamber 10451.The impellers are carried on a common shaft 55a the lower end of whichholds the pulley S5 coupled to the motor by V-belt 52. In one directionof rotation, the upper impeller recirculates water to and from the tub16 and, in the opposite direction of rotation, the lower impeller 194drains water from the tub.

The respective recirculation and drainage systems are best shown inFIGS. 2 and 5. A hose 107 couples the recirculation impeller chamber103a to the lower part of the side of tub 16 during operation of theagitator in the washing operation.

To remove or drain liquid from the tub during the y e spinning of thebasket in the water-extraction operation, reverse rotation of the motoreffects a liquid pumping operation of drain impeller 104. A hose i109couples the drain impeller to a sump 110 at the bottom of tub 16 towithdraw the water from the tub. The wash or rinse water is forced outby the lower impeller into a drain hose 111 land carried to anappropriate drain connection (not shown).

During forward rotation of pump pulley 55 and while upper impeller 103is recirculating water in the tub, the lower impeller 104 is acting soas to draw air through hose 111. As preferably constructed, the lowerimpeller 104 will not draw liquid from the sump 110 during forwardrotation of pump pulley 56.

The present invention is directed to a filter arrangement employed inthe fluid system to clean the laundering fluid and remove foreignmaterial, such as dirt and lint, from wash water and to insure theremoved lint and dirt is prevented from redepositing on the clothesbeing laundered. It is desirable to recirculate the wash water, passingfrom the tub during the washing operation, through a filter to providefor the constant extraction of the lint to clarify the wash water andprevent wide spread distribution of lint onto the clothes in the basket.Also, it is equally important to provide for the automatic removal ofthe lint accumulated by the filter.

Referring to FIGS. 2 and 5, my self-cleaning filter is indicated at Fand is located in the fluid system between the sump 110 and intake portof the pump chamber 103a containing the impeller 103. The filter isconnected to the sump 110 by a hose l112, and the pump chamber 103a isconnected to the filter by a hose 113. Accordingly, during operation ofthe pump in the washing operation, for example, wash water is drawn bythe impeller 103 from the sump 110 of tub 16, hose 112 into and throughthe filter F, hose 113, into the chamber 103a, through hose 107 to thetub 16. The water is thus continuously recirculated -from the tubthrough the filter and returned to the tub during operation of the upperimpeller 103a during the washing operation.

FIGS. 6 and 7 illustrate the structure of the filter F which comprises abell-shaped body 115 having its upper end provided with a collar portion116 inserted within and connected to the end of the hose 112 in fluidcommunication with the tub sump 110. The collar portion l116 forms anentry port of the filter for water flowing through the hose 112 and intothe filter during recirculation of the water by the pump propeller 103.The filter body 115 has its lower end terminating in a radiallyoutwardly extending annular flange 117 engaging the rim of a plate 118and connected thereto by bolts 119 extending through the flange 117 andthreaded into the plate 118. A gasket 120 may be positioned between theflange |117 and plate 118 to prevent leakage of water between the fiangeand plate and from the compartment 122 formed by the body 115 and plate118. The plate 118 has a centrally located tube 121 providing a passagefor water from the filter compartment 122 to the hose l113 connected tothe pump impeller chamber 103a. More specifically, the tube 121 ispreferably formed integral with the plate 121 and to dispose a portion121:1 exteriorly of the plate and extending downwardly to be receivedwtihin the adjacent end of the hose 1113.

Referring to the structure of the filter providing the lintscavengingfunction, the tube 121 of the plate 118 also has a portion 121b whichextends upwardly from the plate and into a frusto-conical cap 123. Asseen in FIG. 5,

the upper end of the tube portion 121b has the radially outer edge ofits rim in contact as at |124 with a diametrically-conforming circularportion of the cap 123 and securely connected thereto by welds 125. Theupper end of the tube portion 121b is provided with circumferentiallyspaced slots 126 providing passages for water from the chamber 122 andinto hose 113. The cap 123 is provided with upwardly extending teeth orprongs 127 arranged in tiers circumferentially of the outer surface ofthe cap and also openings 128 extending through the cap and disposedbetween the tiers of the teeth 127. The teeth 127 of cap 123 extendthrough aligned openings in a conical hood 129. The hood129 is formed toconform its inner surface to the contour of the outer surface of the capso that these surfaces are contiguous and engage each other. Theopenings in the hood 129 are formed sufficiently large, in relation tothe teeth 127, to permit vertical movement of the hood for the purposenow to be described.

In the operation of my improved filter, wash water is constantlyrecirculated by the pump impeller 103, as indicated by the solid arrowsin FIG. 5, the water flowing from the pump into and through the hose 107into the tub, and water is withdrawn from the tub sump 110 and flowsthrough the hose 112 into the filter chamber 122 and from the chamber122 into the hose 113 for return to the pump. Referring to FIGS. 6 and7, lint-laden wash water, fiowing from the tub through hose 112, entersthe chamber 122 of the filter and is directed along the outer surface ofhood |129 and thereby fiows through the teeth 127 of cap 123. The teeth127 are effective to screen the wash water and catch the lint wherebythe trapped lint is prevented from being recirculated with the water.The substantially lint-free water then flows into the interior of thecap 123 and through the slots in the upper end of tube portion 121b andthence through the tube portion 121a into hose 113.

An important feature of the filter is the provision for automaticallycleaning thelint from the filter one or more times during each use of anautomatic washer 0f the water recirculating type described. In thisoper-ation,

the lint is removed from the teeth 127 of the cap 123 and is flushedfrom the filter and directed to a drain when the lint is still wet andmay be readily fiushed from the teeth. More particularly, the lint iscontinually scavenged from the water during phases of operation of theautomatic washer in which the water is recirculated by the pump. Uponeach conclusion of these operational phases, the direction of rotationof the drive motor 41 is reversed with the consequence that the rotationof the impeller 103 is also reversed and thereby the flow yof water isdirected toward the filter by the pump` More particularly, and asindicated by the broken arrows in FIG. 5, w-ater is drawn from the tubthrough hose 107 into the pump by the impeller 103 and is discharged,under pressure, into hose 113 connected to the filter. The water liowsupwardly through the tube 121a and is expelled from the upper end of thetube with considerable force to impinge against the inner conicalsurface of the cap 123. As a consequence, water is ejected through theopenings 128 of the cap and against the inner surface of the hood 129,norm-ally closing these openings during filtering, as to move the hoodupwardly thereby causing lin-t to be stripped from the teeth, It will beapparent that concurrently, a substantial quantity of water flowsthrough the slots 126 of the tube 121b and along the inner surface ofthe cap 123, between the spaced facing surfaces of the cap and hood, andalong the outer surface of the hood 129 to flush the lint through the,collar portion 116 of the filter body into and through the hose 112.The lint-laden water flows into the sump 110. As the reversal of themotor direction has caused the impeller 104 to become operative towithdraw water from the sump and thereby from the tub, the lintladenwater, from the filter, flows into the sump and even through the hose109, the pump chamber 10411, `to the drain so that there is nopossibility of the lint returning to the tub.

To limit the upward movement of the hood 129 to a position effective toclear the lint from the teeth 127 while retaining the hood on the teethfor later downward gravitational return movement on the cap, the apex ofthe hood is provided with a cross-shaped portion 131 operative to engagestops 130 formed integral with the bell-shaped body 115 andcircumferentially spaced to be in alignment with and thereby engage thearms of the cross-shaped portion 131 of the hood during raising actionof hood by the flushing action of the water.

While a detailed disclosure of a preferred embodiment of the inventionhas been provided, it will be obvious that the invention is not to belimited to the specific form disclosed, as it is susceptible of Variousmodifications, changes and alternative constructions coming within thescope of the appended claims.

What is claimed is:

1. In a self-cleaning filter, la fluid container having first and secondports; a fixed member in said container and having openings extendingtherethrough; .a movable member telescoped on said fixed member anddisposed in the path of fluid from said first port, said movable memberhaving openings extending therethrough and said fixed member havingfiltering projections extending through the openings in said movablemember; means providing for the flow of linteladen fluid under pres*sure through said first port, through said filtering projections tofilter said fluid of lint, and through said second port; and meansproviding for the flow of fluid under pressure through said second port,through the openings in said fixed member to forcibly move said movablemember to strip lint from said filtering projections and to dischargethe lint through said first port.

2. In a self-cleaning filter as defined in claim 1 wherein said fixedand movable members are cup-shaped; and wherein lint-laden fluid,entering said first port, flows along the outer surface of the movablemember and through the filtering projections of the fixed member.

3. In a self-cleaning filter, a fluid container having first and secondports for passage of fluid through said container; a first cup-shapedmember in said container and having openings extending therethrough; asecond cup-shaped member positioned on and telescoping said first memberand disposed for flow of fluid lalong the exterior surface thereof, saidsecond member having openings extending therethrough and said firstmember having teeth projecting through the openings in said secondmember; means for effecting the flow of lint-laden fluid through saidrst port, said teeth to filter said fluid of lint, and through saidsecond port; and means for forcing fluid through said second port,through the openings in said first member to move said second memberalong said teeth to scavenge lint from said teeth, and to discharge thelint through said first port.

4. In a self-cleaning filter, a fluid container having first and secondports; a first conically-shaped member in said container and having itsapex directed toward said first port, said first member having openingsextendinng therethrough; a second conically-shaped member telescopingsaid first member and having its exterior surface disposed for flow offluid from said first port along said surface, said second member havingopenings extending therethrough and said first member having teethprojecting through the openings in said second member; means providingfor the flow of lint-laden fluid through said first port, along theexterior surface of said second member and through said teeth to filtersaid fluid of lint, and through said second port; and means for forcingfluid through said second port and through the openings in said firstmember to move said second member relative to said first member toscavenge lint from said teeth, and to discharge the lint through saidfirst port.

5. In a self-cleaning filter, a fluid container having upper and lowerports; a first generally conical fixed member in said container andpositioned to dispose its apex beneath said upper port, said firstmember having openings extending therethrough; a second generallyconical member telescoping said first member and disposed to interceptfluid entering said first port for flow of fluid along the exteriorsurface thereof, said second member having openings extendingtherethrough, said first member having teeth projecting through theopenings in said sec* ond member; means providing for the flow oflint-laden fluid through said upper port, along the exterior surface ofsaid second member and between said teeth to filter said fluid of lint,and discharge the fluid through said lower port; and means providing forthe flow of fluid through said lower port and into the interior of saidlower member and through the openings thereof to raise said upper memberto scavenge lint from said teeth, and also along the outer surface ofsaid second member for the discharge of lint through said upper port.

6. In a self-cleaning filter as defined in claim 5 wherein said secondmember overlies the openings in said first member, asd means areprovided to direct the fluid from said lower port into said openings insaid lower member.

7. In a self-cleaning filter, a fluid container having an upper port,said container having a tubular portion projecting into the interior ofsaid container, the lower end of said tubular portion defining a lowerport of said container and the upper end of said tubular portion havingfluid passages; a first generally conical fixed member in saidcontainer, said tubular portion extending into said first member andsaid first member being positioned on the top of said tubular portion todispose the apex of said fixed member beneath said upper port, saidfirst member having openings extending therethrough; a second generallyconical member on said first member and disposed to intercept fluidentering said first port for flow of fluid along the exterior surfacethereof, said second member having openings extending therethrough, saidfirst member having filtering projections extending through the openingsin said second member, said members being in spaced relation to saidcontainer to provide for flow of fluid between said container and saidmembers and through said fluid passages in said tubular portion of saidcontainer; means providing for the flow of lint-laden fluid through saidupper port, along the exterior surface of said second member and throughsaid filtering projections to filter said fluid of lint, and dischargeof the fluid through said lower port; and means providing for the flowof fluid through said lower port, and said tubular portion into theinterior of said lower member, and through the openings there-of toraise said upper member to scavenge lint from Said filteringprojections, and also along the outer surface of said second member forthe discharge of lint through said upper port.

'8. Ina self-cleaning filter as defined in claim 7 wherein the upper endof said tubular portion of said container is provided with slots todefine said fluid passages.

9. In a self-cleaning filter as defined in claim 7 wherein saidfiltering projections are teeth on said first member.

References Cited UNITED STATES PATENTS 2,439,535 4/1948 Wilson 210--4072,555,725 6/1951 Archbold 210-407 X 3,286,841 1l/1966 Dinglinger 210-407X REUBEN FRIED'MAN, Primary Examiner.

F. MEDLEY, Assistant Examiner.

1. IN A SELF-CLEANING FILTER, A FLUID CONTAINER HAVING FIRST AND SECONDPORTS; A FIXED MEMBER IN SAID CONTAINER AND HAVING OPENINGS EXTENDINGTHERETHROUGH; A MOVABLE MEMBER TELESCOPED ON SAID FIXED MEMBER ANDDISPOSED IN THE PATH OF FLUID FROM SAID FIRST PORT, SAID MOVABLE MEMBERHAVING OPENINGS EXTENDING THERETHROUGH AND SAID FIXED MEMBER HAVINGFILTERING PROJECTIONS EXTENDING THROUGH THE OPENINGS IN SAID MOVABLEMEMBER; MEANS PROVIDING FOR THE FLOW OF LINT-LADEN FLUID UNDER PRESSURETHROUGH SAID FIRST PORT, THROUGH SAID FILTERING PROJECTIONS TO FILTERSAID FLUID OF LINT, AND THROUGH SAID SECONE PORT; AND MEANS PROVIDINGFOR THE FLOW OF FLUID UNDER PRESSURE THROUGH SAID SECOND PORT, THROUGHTHE OPENINGS IN SAID FIXED MEMBER TO FORCIBLY MOVE SAID MOVABLE MEMBERTO STRIP LINT FROM SAID FILTERING PROJECTIONS AND TO DISCHARGE THE LINTTHROUGH SAID FIRST PORT.